A steering column lock failure solution

Hello fellow Sprinter owners. Its been a while for me. 2 years ago we moved to the mountains of North Carolina, away from the bustle of the Northeast, and even further from the nearest MB Sprinter servicing dealer. Needless to say I have started doing nearly all my own maintenance. What I wont or cant do I am lucky enough to have a great independent shop in my town that really seems to know their way around the NCV3.

Recently my '12 Sprinter exhibited the 'steering column wont unlock' symptom. It occurred 3 times over as many days and I was able to temporarily resolve the symptom each time by removing and reinserting fuse F2.

There didnt seem to be a mechanical problem such as a key issue or the steering column turned against the locking bolt holding it, or electrical such as battery low or key chip detection. Indeed when I had the van scanned by my local independent service guy (Eurotechnic of Hendersonville), a couple of the codes suggested the hall sensor inside the steering column lock module, that detects the position of the column locking bolt may be malfunctioning or the bolt hanging up (his words - I didnt see the actual codes).

After the 3rd incident I removed the column lock.

Here is a tip: You CANNOT remove the lock if has failed in the lock position. Once that is the case you either have to replace the steering column along with a new lock module, somehow get the module to unlock one more time, or perhaps drill one or more holes in the module and use a pick or something to manually turn the motor/gear to back the bolt back to the unlock position. I have no idea if this can be done with this model module but I saw videos of it done on some other versions on various MB vehicles.

To remove the lock module the easy way:

1) Turn on the ignition so the steering column module unlocks.
2) Unplug the electrical connector from steering column lock module.
3) Turn off the ignition. The lock is now in the unlocked position and will stay this way.
4) Find the T30 headed pin on the casting of the column that holds the lock module and rotate it CW180 degrees. It is located on the steering wheel end of this casting and on the fuse box side. It should be fairly easy to turn. If not, the column lock bolt has not been retracted. Turning it the 180 CW slides a little flag on the pin out of a pocket on the casting and (if the column lock bolt has retracted) the pin can now be removed...You may need to use a small screwdriver and going in from a hole maybe 3/8" diameter on the other side of the casting from the T30, push it part way out.
5)The lock assembly should just swing/fall out. My van has a small vent duct that runs under the steering column and I had to remove the screw at the outer end of it and swing the duct down a couple inches to let the lock module swing far enough down to come out.

Now that you have the old lock module out, you could replace it with a new one, or do what I did. I replaced it with a column lock module emulator. While this no longer locks the column, it also has no moving parts or hall sensors to fail in the future, leaving you with a 7000 pound brick, hundreds of miles from the nearest Sprinter dealer (like me).

Obviously removing the lock and setting aside isnt the end of the story. The van wont start without one. In my case, and since the lock was failing intermittently, I plugged the connector back in and zip-tied the lock to the back side of the dash so I could use the van while I looked for my solution.

The first thing that I though about was getting a new replacement. I got the part number off the old unit and searched the web. Every MB dealer based web parts source shows the part as discontinued. None of the independent sources even list it. I did find a source on eBay from Jacksonville that had 5 to sell at $195 each. Mostly I found used units. I have a used unit. Thats the problem. They wear out. I am not 100% sure but I suspect a new module will also need to be "adapted". Without trying to second guess why MB is drying up the availability, I concluded that I wanted to not replace it with another identical new unit but to find an alternative it at all possible (sort of what I would like to do with the whole damned emissions system).

After searching the web for an alternate solution I came across a couple videos of a module used in Europe (and one in the US) to bypass or emulate the lock module. The module has no moving parts and does not lock the column, it just satisfies the vans anti-theft logic that the column is unlocked or locked at the appropriate times. The US videos is by an independent repair guy in Dallas by the name of Martin Galvan. He sells this module (or one very much like the one I saw in the Euro videos). It is plug-and-play (no "adapting" by a dealer scanner needed). Just connect it up to the plug you took out of the original lock module and hide it somewhere. By the way some of the videos show a 3 wire pigtail that you plug into the corresponding wires on the Sprinter plug...his module cleanly accepts the Sprinter plug into it. No muss, no fuss, no mistakes. You can find Martin on Facebook (Martin's Mobile) or email galvan890@gmail.com. Super responsive. Check reviews on Yelp if you want.
 

sprint2freedom

2008 NCV3 170ext
Very interesting to hear about your experience using an emulator. Thanks for the write-up!

I have no idea if they're any good but a search turned up some Chinese offerings:

https://www.aliexpress.com/item/32978654003.html
https://www.aliexpress.com/item/32975394632.html

At ~$30 it's almost worth getting one of these before the problem even develops as cheap insurance prior to reaching the point of '7000 pound brick'.

I found this video showing the type of module that has the 3 wire pigtail being used:
https://www.youtube.com/watch?v=kQw3JcevbZs
 
Brief update. I just completed a trip of about a week in which I started the Sprinter maybe 2 dozen times. Not a single glitch. Only thing different is not hearing the column lock ziiiip locking and unlocking. But I can now hear the very low volume chirp of the ignition lock maybe 1/2 second after the key is inserted or removed doing its thing.
 
One of the first issues someone might encounter with a failed steering column lock is that you cannot remove the lock assembly from the column if it will not unlock. This will normally result in having to replace the column and lock as a set. I believe this is how MB service does it which is great if you are spending someone else's money.

I was lucky enough to have it work (unlock) one last time when I turned my ignition switch on, whereupon I unplugged it so it would not relock. I was able to remove it by simply turning the Torx headed assembly retaining rod (see picture 4) and pulling it out. This torx head rod is locked in place when the assembly is also locking the steering column by the same "locking bolt" in the assembly. As I am completely comfortable with the emulator module I installed in place of my original lock assembly, I recently decided to dig into the original lock to see how one might force it unlocked while still on the column, thus making it removable and freeing up the steering column.

The lock bolt is driven by a DC motor and ignoring the electronics that drives it, I am able to feed between 5 and 12V at about .75A directly to the motor to drive it unlocked or locked. It required 2 1/8" holes be precisely drilled into the plastic end cap of the motor to reach the power leads to the motor itself. That is probably not practical for most people to try due to the orientation of the lock when in the vehicle, and if the problem to begin with is the motor has failed or is stuck, you havent solved anything. Not to mention, I drive the motor with its PCB removed and I dont know how it would behave if it were still in place and the motor connected to 12V and ground. I only mentioned this in case someone wonders if it is possible to separately run the motor to unlock the assembly. It is possible.

The next approach I took is purely mechanical. The goal is to access and remove the mechanism that is the lock bolt itself. Picture 1 shows the cover (circled in red) that needs to be removed. It is held in place by being staked with 4 small hollow steel pins. In picture 1 you can see the raised bits in the cast housing and cover on the right that are where 2 of the pins are inserted. The other 2 are on the left side. I used a 1/8" drill to drill away the pins. The exact size drill isnt important so long as it isnt so small the pins arent drilled out nor so large the drill wont pilot itself down the center of the hollow pin. You need a good strong and sharp bit. You only need drill deep enough to remove the part of the pins between the cover and the housing...maybe 1/4-3/8". Other bits such as end cutting carbide would also work. Another approach might be to cut into the joint of the cover and housing at each pin with a abrasive circular wheel on a Dremel or similar tool. I went with the drill followed by the carbide bit.

Once the pins have been drilled or cut away, you should be able to pry the cover off and there you should see the contents such as in picture 2. At this point you should be able to simply pull up on what looks like a button in the middle of the black plastic gear (that is actually the back end of the locking bolt), and remove them both. When the lock assembly is in the locked position, the plastic gear can be lifted off by itself, but anywhere else the lock bolt and plastic gear will be engaged by a pin and have to come out together.

Picture 3 is with all the mechanical parts removed and separated.
 

Attachments

It's not strictly true that the steering column has to be replaced when the lock module fails in the locked position. A number of people have used a dremel tool to either cut the module off of the column, or cut it open to persuade it to unlock. It's not only a question of unlocking the column, because the module also has to send a confirmation message over the data bus. If the module is replaced it needs to be coded to the vehicle. One option to bypass that is to get a new module and swap in the circuit board from the old module. My response to all of this many years ago was to remove the module and zip tie it to the side of steering column. A reliable emulator does seem like the best solution. There used to be pictures of all of this but they were hosted on photo sites that aren't there any more. A big thread about this problem started 11 years ago, with the newly found "cut it off" method starting on the 4th page: https://sprinter-source.com/forum/showthread.php?t=6885l&page=4
 

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